They must be chatting on the Internet.
You shouldn’t be working like this.
EXERCISES
一、用适当的情态动词填空
1. You needn’t worry about me.
2. He looks so pale, he must be ill.
4）表示推测，意为“想必一定、照说应 该、估计”等。 He should be free by now.
7. ought to
1). 表示义务, 作“应当”讲, 语气比should强烈
As a student, you ought to study hard.
You oughtn’t to speak so much.
4). needn`t have done 用于否定句 表示过去“本来不需要……”
You needn’t have worried about me.
你本不必为我担心。
情态动词后面跟进行时
情态动词 + be + doing
表示“想必正在……”，“可能正在……”，“应当正在”
They may be discussing our problem. She can’t be telling the truth.
You must have gone swimming, for your hair is wet now.
2). may have done 和 might have done 也许、 或许、已经
表示对过去所发生动作的推测, 常用于肯定句 或否定句。
I’m not sure. He might have invited you.
2. 表示遗憾、后悔或责备
1). should have done 和 ought to have done
用于肯定句表示“本该做某事, 而实际 上没有做”
You should have given her a hand just now.
用于否定句表示“本来不该做的事反而 做了”。
You oughtn`t to have invited him.
This kind of thing will happen.
这种事情总是要发生的
He would stay up late when he was young.
4）.表示“注定会”
Fish will die without water.
5. shall
1).用于第一人称和第三人称的疑问句,
表示征求对方的意见.
委婉、客气.
Will / Would you please open the window?
2）.表示意志或意愿
I will help you.
He promised that he would do anything for you.
3）.表示习惯, will表示现在的习惯, 意为“总 是; 习惯于”。would表示过去的习惯性动作.
7. He daren’t come to see you again.
8.We ought to help parents with housework.
二、单项选择：
1. You A fail in the exam without hard working.
A. will B. would C. mustn‘t D. can
can /could
can只有现在式和过去式
(could), 表示一般能力
can / could /
be able to
用于多种时态， be able to was/were able to表示曾
经通过努力而做成某事
You needn’t worry about me.
情态动词
主要用法
Yowuounldeed表无n示跟’t过当w去前o习对rr惯比y 性之ab或意o重ut复m性e的. 动作,并
比 can语气更委婉,回答用原形。
Could you tell me how I can get to the zoo?
4).表示推测“可能”(用于疑问句和否定句)
She can’t be our headmaster. She has gone to
America.
2. may/might
1).表示请求、允许、许可, might比may的语
2). 表示含蓄或不完全肯定的推测, 意为“应该”或 “应是”
He ought to . dare.
用于疑问句、否定句和条件状语从句中,表示 “敢; 敢于”。
She daren`t go alone at night.
How dare you come again? Go if you dare.
A. can B. may C. ought to D. could
9.You A waken me up, it`s Sunday today. A. needn’t have B. must have C. need have D. mustn`t have
10.I hope that everyone B pass the exam. A. can be able to B. will be able to C. would be able to D. are able to
3. Plants will die without sunshine.
4. The red coat can’t . be Bob`s , he doesn`t like red at all.
5. We should learn from each other.
6. Miss Li would help me when she worked at our school.
2. He had to give up smoking because of his illness, C he?
A. did B. does C. didn’t D. doesn‘t 3. —May I wear jeans to take the party?
—Sorry, you B ,you should wear a suit.
2)表示惊讶、意外, 作“竟然”讲
To my surprise you should not know about me.
3) 表示可能性很小, 但并非完全不可能，用于if 引
导的条件状语从句。
If he should be free yesterday, he would come to our party.
11. — Don't eat in class.
—___C___
A. Yes, I won't.
3). can have done 和could have done 表示对过去所发生动作的怀疑和否定, 通 常用于否定句和疑问句
Where can Tom have gone?
I saw Li Lin playing football just now. He couldn’t have been ill.
Shall we go out for a walk?
Shall he wait for you at school?
2).用于第二人称和三人称的陈述句, 表
示“命令、警告、允诺或威胁”.
You shall do as the teacher says.
(表示命令)
You shall receive my money tomorrow.
6. There goes the bell, We'd better A speak .
A. not B. not to C. won't D. don't
7. Students D tell lies.
A. may not B. must C. can D. mustn`t
8. We C follow the rules here.
(表示允诺 )
He shall be sorry for his behavior one day, I tell you. (表示警告 )
6. should
1)表示劝告和建议, 意为“应该”
We should help each other. You should be polite to the old.
含情态动词句型基本结构
陈述句 ： 主语+情态动词+ 动词原形
We should study hard.
一般疑问句 ： 情态动词+主语+ 动词原形
Can you help me?
特殊疑问句：特殊疑问词+情态动词+主 语+动词原形
What should I do?
考纲情态动词用法详解 1、can与could的用法
would/ used toYou need强n调’t跟w现o在rr对y 比ab，o表ut示m过e去. 经常发
used to 生的动作或存在的状态, 表明“现在
不再以前那样了”
情态动词后面跟完成时 情态动词+have done的用法
1.对过去的推测
1). must have done表示对过去已经发生的行 为进行推测, 意为“准是、想必、一定做了某 事”, 通常用于肯定句。
9. need
表示“需要; 必要”, 用于疑问句、否定句和 条件状语从句。
You needn’t worry about me. Need I give you a hand?
Need I help you if you get into trouble?
容易混淆的情态动词 用法区别